The present disclosure relates to an upper structure of a vehicle engine.
Japanese Unexamined Patent Publication No. H11-348579 describes an upper structure of a vehicle engine. This upper structure (an exhaust system cooling structure) is used in a so-called front intake and rear exhaust engine, and includes a design cover (an approach plate) provided over a head cover (a rocker cover). This design cover is arranged with a gap interposed between the design cover and the head cover, and has a lower surface having a rear end portion inclined toward an exhaust device (an exhaust passage). In the upper structure, an air stream produced by a traveling vehicle passes through the gap between the lower surface of the design cover and the upper surface of the head cover, and is guided to the exhaust device by the inclination of the lower surface of the design cover. Thus, the exhaust device can be effectively cooled.
For the upper structure described in Japanese Unexamined Patent Publication No. H11-348579 described above, when no air stream is produced by a traveling vehicle, such as when the vehicle is at rest, hot air rising from the exhaust device may flow into the gap between the design cover and the head cover.
An upper surface of a head cover is usually provided with parts, such as a harness. Thus, if the hot air flows into the gap as described above, such parts may be exposed to the hot air, resulting in inconvenience, such as erosion of such parts.
To address this inconvenience, the gap between the design cover and the head cover may be blocked to prevent hot air from flowing into the gap. However, such a configuration is not suitable for cooling the exhaust device with the air stream described above.
Such an unsuitable configuration is not limited to a configuration including a design cover, but is common to general configurations including various members arranged above the head cover.
In view of the foregoing background, one or more aspects of the present disclosure is directed to an upper structure of a vehicle engine that cools an exhaust device with an air stream produced by a traveling vehicle while protecting parts provided on an upper surface of an engine.